In this paper, the authors propose a new Power Efficient Clustering Protocol (PECP) for prolonging the sensor network lifetime. Homogeneous clustering protocols assume that all the sensor nodes are equipped with the same amount of energy and as a result, they cannot take the advantage of the presence of node heterogeneity. Adapting this approach, they propose a new protocol named PECP (Power Efficient Clustering Protocol) to improve the stable region of the clustering hierarchy process using the characteristics parameters of heterogeneity, namely the fraction of powerful nodes (with more energy) more suitable to become a cluster head.